kevin519 wrote:
So I was thinkin this mornin, most will agree for portraits an 85mm is best, some will say other lens', but for the most part an 85, but what about the crop vs FF body? So what if you use a 50mm, with a crop of 1.6 that puts you at 80mm right, and the 85 at 136, so now what? So is it the mm, or the f/???, or is it in the way the 85mm is built, I just dont know. I have a fast 50L lens, and a 2.8 70-200 which can hit that 135mm spot easy, so why would I buy a 85mm?
I've skipped past most of the responses (well quick scan), but the issues appear to be as follows:
- You have a Canon 60D I think, so APS-C format.
- If so, then the field of view becomes important, and a 50mm lens APS-C is roughly equivalent to 85mm on 35mm/FF, the classic 'portrait lens' for 35mm cameras. Or perhaps a 135mm, the next common step in many prime lens families.
- Another factor is the max aperture size of the lens in terms of DOF. For portraits ability to control a narrow DOF and also have decent 'bokeh' for out of focus backgrounds seems to be considered important.
- From a FOV perspective, a 50mm lens would deliver a 'classic portrait lens' character on an APS-C body, but a max f/2.8 aperture (or zoom compromises in lens design) would not necessarily deliver the DOF or 'bokeh'. There are several considerations to take into account.
I have an old manual focus Canon FL 55mm f/1.2 lens (circa 1970) adapted to an EF mount, which fits the classic 'portrait lens' profile quite well, and is fun to use. Also an FDn 135mm f/2.0 adapted which also can deliver interesting results.
DOF seems to be a factor in portraits, so consider aperture and number of aperture blades as well as focal length of the lens.
Another factor is that expectations of a good portrait differ. Some like really crisp detail, some like a softer approach. It gets complicated, and the distance of photographer to subject affects the relationship dynamic....
Lots to think about!